The overall goals of the proposed experiments are to investigate the function that the cerebellum plays in guiding coordinated motor behavior. Present theories of cerebellar function are derived from 2 separate sources, i.e., insights gained from clinical observations on cerebellar patients and neurophysiological investigations on anesthetized animals. The goal of this project is to bridge this gap by investigating coordinated motor behavior and cerebellar neuronal firing patterns in the awake cat. It is expected that this investigation of 2 qualitatively different motor systems (skeletal musculature and oculomotor) will help to elucidate cerebellar function more completely. The investigation in the skeletal musculature will deal with the influences of sensory (cutaneous and proprioceptive) input to cerebellar neurons and their relationship to the performance of ballistic and non-ballistic forelimb motor tasks. Thus, long term multifaceted investigations on the firing patterns of individual cerebellar neurons will be conducted during a variety of sensory and motor manipulations. A complementary study will deal with the investigation of oculomotor behavior and cerebellar neuronal firing patterns. Unit activity will be correlated with spontaneous, optokinetic induced and conditioned eye movements. A computerized multi-correlation method will be used to compare neuronal firing patterns with behavioral and physiological parameters. BIBLIOGRAPHIC REFERENCES: Waterhouse, B.D., Mays, L.E. and McElligott, J.G. Cerebellar unit activity in the awake and unanesthetized cat during spontaneous eye movements. Soc. for Neuroscience 6: 119, 1976. McElligott, J.G. and Waterhouse, B.D. A microelectrode implantation technique for use in the awake and unrestrained cat. Physiology and Behavior 18: 1977.